By John Dodge

CHICAGO (CBS) — The crash of Malaysia Airlines MH17 appears to be caused by a missile strike, according to U.S. officials, but both sides in the fighting in southeastern Ukraine are denying responsibility.

So as of Friday morning, what do we know?

Experts say the crash scene, and the fact that the MH17 crew did not radio a distress signal, appear consistent with a ground-to-air missile attack. U.S. intelligence indicates the missile was fired from the area of Ukraine that is under the control of Russian-backed rebel forces, President Obama said at a news conference on Friday.

“This was a global tragedy,” Obama said.

The key is analyzing data from the plane’s fight data recorders, but as of Friday morning it was uncertain who had possession of those boxes.

Russia, which has been supporting the pro-Russian separatists in the region, denied any responsibility.

Ukraine’s government is accusing the rebels of shooting down the plane with a Russian-made missile system.

The rebels blame the Ukraine government for the catastrophe. The Russian separatists want to secede from Ukraine and align with Russia, the country’s neighbor to the east.

According to the Associated Press, the U.S. believes the missile was fired by the rebels.

So as of now, we know that there is a lot of blame going around.

We do know that there are no survivors from the plane, which was flying at 33,000 feet when it disappeared from radar around midday, Chicago time.

Initially, reports said there were 295 people on board. That number has been changed to 298 as of Friday. Also there were reports on Thursday that as many as 23 U.S. residents were on the flight.

President Obama said one U.S. citizen was on the flight–Quinn Lucas Schansman. The hometown or other details were not immediately available.

Indiana University also has confirmed doctoral student Karlijn Keijzer was a passenger on the flight.

Keijzer, 25, was a doctoral student from Amsterdam in the university’s chemistry department and also earned her master’s degree at IU. She was on the rowing team during the 2011 season.

The final location of flight MH 17.

The final location of flight MH 17.

There is also the question of why Malaysia Airlines chose to fly over a war zone. According to, two other planes were also flying in the area when MH17 crashed.

Malaysia’s government said the route has been used by several other airlines recently and that international aviation groups had not declared the route dangerous.

On Friday this image from Flight Radar’s website, captured at 8:30 a.m. Chicago time, shows that airlines were clearly flying around the southeast region of Ukraine where the fighting is occurring.